As a general rule of thumb, semantics (such as visual detail) only matter if you can do something with them, and make the reader care about their inclusion.
How you describe your SCP largely depends on what you want to achieve with it. Do you plan to utilize later on in a narrative sense? Are you trying to evoke some kind of body horror? Is it just because you want it to look cool?
If you want to utilize it later on, I'd say keep it relatively short, but long enough so that the reader can say "hey, I remember that from the description!" when they reach the narrative point, which will heighten the article. If you're trying to evoke horror in some sense, you can make it longer, as you're trying to evoke the emotion in the text right then and there. If it's just for the sake of being cool, you can gloss over it, but it may be worth asking yourself if it's even worth including.
It'll mostly be trial and error guiding you here, so just experiment with what works and what doesn't. Reading more works that include heavy physical descriptions is also a good option.
